Establishment And Applications Of The Three-dimensional Nasal Morphological Database In Han Ethnicity

The nose is located in the central part of the face, and its appearance contributes enormously to facial aesthetics. As a result, the reconstruction of nasal defects requires high quality of morphological simulation. Wax models of traditional nasal prostheses were carved by hand, which was low quality and low efficiency. Recent years, CAD/CAM technology has been an alternative to traditional methods for the reconstruction of facial defects. This technology has various advantages and will be routinely used in clinical. In the CAD procedure of restoration of a patient with the defect of the bilateral organs, it is easy to cover the defect area by mirroring the healthy side. However, if the patient has the defect of nose, it is hard to find a proper nose for design of the prosthesis. The purpose of this study was to establish a database of 3D models of nasal shapes, which was aimed to meet the need of CAD nasal prosthesis.As to the contents, this study contained two main parts. The first was the establishment of database, and the second was the applications of the database. The follows were the main contents and the results of this study.1. Data Acquisition was the first procedure of the establishment of database. This study intended to use the computed tomography and 3DSS-â…¡to acquire nasal data. As to the reliability and accuracy of facial reconstruction, there have been some reports on the CT, but the related researches on 3DSS-â…¡were insufficient. So reliability and accuracy of 3DSS-â…¡in reconstruction of facial images were tested at first. The results show that the reliability of 3DSS-â…¡was no less than the direct measurement, and the accuracy of 3DSS-â…¡has no significant difference with direct measurement. In conclusion, 3DSS-â…¡could be used to acquire nasal data for the database.2. The following procedure was the acquisition of 3D nasal morphological data. As a result, 1000 nasal models were collected by 3D reconstruction of the existed CT data, and 200 nasal models were collected by3DSS-â…¡.3. There were so many nasal models, that we might be overwhelmed with these data. Therefore, there was an urgent need to develop database software to organize these models. In this study, the software were based on Microsoft Office Access, and were written by Microsoft Visual C++. OpenGL were used to realize the visualization of three-dimensional data. In this procedure, nasal shape classification must be mentioned. Until now, there have been many different classifications, but no unified classification, and no one classification can include all nasal shapes. On this condition, multiple classifications were integrated to develop our database. In this way, the database could contain most of the nasal shapes. With the help of the software, nasal models could be imported into the database accompanied with their morphological features, and people could easily find the proper models for their certain needs. 4. When all the nasal models were imported into the database, the establishment of database was finished. As follows, the application of the database was conducted. One application is the clinical use for restoration of the patient with nasal defect. Searching for proper nasal model is an indispensable step of the restoration of nasal defect with CAD/CAM. In this study, the procedure of selecting a proper nasal model for a patient with nasal defect was introduced, and the result showed that the usage of the database was an efficient solution to the problem of lack of references in the process of CAD restoration of nasal defect.5. To make full use of the database, this study applied it to nasal anthropometry. In this database, many three dimensional nasal models were sorted in particular classifications. Therefore, it was possible to conducted 3D anthropometry without recruitment of volunteers. In this study, a novel method for nasal anthropometry was introduced, and 3D standard models representing nasal shapes were created. Compared with traditional 2D parameters, these visualized 3D standard models facilitated the comprehension of the nasal morphology. It would provide useful guidance for the researchers who needed the information of nasal shape.